Engineered ADU Foundations Built Right From the Ground Up
Functional Concrete Artistry builds detached and attached ADU foundations, slab-on-grade systems, stem walls, grade beams, footings and structural concrete from approved plans with careful coordination of excavation, reinforcement, inspections and concrete placement.
One Contractor for Excavation, Footings, Reinforcement and Concrete
The foundation is the most important structural phase of an ADU project. Errors in layout, elevation, footing depth, reinforcement or utility coordination can affect every trade that follows. Our work is organized around approved drawings, field dimensions and required inspection points.
- Site layout and elevations
- Footing excavation
- Stem wall formwork
- Grade beams
- Slab reinforcement
- Vapor barriers
- Utility coordination
- Concrete placement
Real ADU Foundation Work From Excavation Through Reinforcement
Every photo below shows a different phase of foundation construction. Each image is used once with no repeats.
Foundation Systems for Detached, Attached and Converted ADUs
Slab-on-Grade
Integrated slab and footing systems used for many detached and attached ADUs.
Stem Wall Foundations
Continuous footings and raised perimeter walls that support the floor system above.
Grade Beam Foundations
Reinforced beams connecting structural supports and carrying concentrated loads.
Garage Conversion Foundations
Foundation modifications, infill and structural concrete for converted garage areas.
Attached ADU Foundations
New foundations coordinated with existing structures, elevations and connection details.
Detached ADU Foundations
Complete foundation construction for backyard cottages and freestanding units.
Raised Floor Foundations
Footings, piers and stem walls for approved raised-floor construction.
Structural Concrete Walls
Reinforced walls used where plans require grade retention or below-grade support.
A Clear Sequence From Layout to Framing Release
Plan Review
Confirm dimensions, details, reinforcing and required inspection points.
Site Layout
Establish footprint, setbacks, benchmarks and foundation elevations.
Excavation
Excavate footings, grade beams and slab areas to the approved depth.
Forms & Steel
Install forms, reinforcement, dowels, chairs and embedded components.
Utilities
Coordinate plumbing, sleeves, conduits and under-slab penetrations.
Inspection
Prepare the foundation for required jurisdictional and project inspections.
Concrete Placement
Coordinate delivery, pumping, placement, consolidation and finishing.
Cure & Strip
Protect the concrete, remove forms and complete edge cleanup.
Backfill
Backfill approved areas and prepare the site for the next trade.
Framing Release
Turn over a clean, ready foundation for framing to begin.
Accurate Excavation Creates the Base for Everything That Follows
Foundation excavation must match the approved plans while accounting for access, soil conditions, existing improvements and utility locations. Footing bottoms should remain clean and undisturbed before reinforcement and concrete placement.
- Foundation trenching
- Slab-area excavation
- Export and haul-off
- Base preparation
- Elevation verification
- Utility trench coordination
Rebar Placement That Follows the Engineering
Reinforcement is installed according to the approved structural drawings. Bar size, spacing, laps, hooks, dowels, chairs and concrete cover all matter. The steel must remain securely positioned during inspection and placement.
- Continuous footing steel
- Grade beam cages
- Vertical stem-wall bars
- Slab reinforcement
- Dowels and lap splices
- Chairs and concrete cover
Structural Concrete Experience With Jobsite Accountability
Licensed C-8 Contractor
Concrete work performed by a licensed California concrete contractor.
Plan-Driven Work
Construction organized around approved structural and architectural drawings.
ADU Experience
Foundation construction tailored to attached, detached and conversion projects.
Inspection Coordination
Foundation phases prepared for required inspections before placement.
Rebar Expertise
Careful installation of footing, wall, beam and slab reinforcement.
Schedule Awareness
Work sequenced to support plumbing, inspection, concrete and framing milestones.
Clear Communication
Updates regarding progress, field conditions and decisions that affect the work.
Clean Turnover
Forms, debris and affected areas addressed before the next trade begins.
The Quality Is in the Preparation
Vapor Barrier
Under-slab vapor protection installed with properly overlapped and detailed seams when specified.
Plumbing Penetrations
Openings and utility penetrations coordinated before concrete placement.
Anchor Bolts & Holdowns
Structural embeds positioned according to approved framing and foundation details.
Concrete Strength
Concrete mix selected according to the project specifications and approved plans.
Elevation Control
Top-of-wall and slab elevations checked to support framing and finish transitions.
Curing & Protection
New concrete protected from premature loading while strength develops.
Answers to Common Foundation Questions
How much does an ADU foundation cost?
Cost depends on footprint, foundation type, excavation depth, soil conditions, access, reinforcement, utilities, concrete quantity, engineering details and haul-off requirements. Approved plans are the best basis for an accurate proposal.
Do I need engineered plans?
Most ADU foundation work is constructed from approved architectural and structural plans. Requirements depend on the jurisdiction, design and site conditions.
How deep are ADU footings?
Footing depth and width are determined by the approved plans, soil conditions, wall loads, frost considerations and local requirements.
What inspections are required?
Inspections commonly include footing or foundation reinforcement, underground utilities, vapor barrier and final foundation items. Exact requirements vary by jurisdiction and project.
Can you perform the excavation?
Yes. Excavation, haul-off and foundation preparation may be included in the scope depending on access and project conditions.
Can you install the rebar?
Yes. Footing, stem-wall, grade-beam and slab reinforcement can be installed from the approved structural drawings.
Can you coordinate the concrete pump?
Yes. Pump access, hose path, delivery sequence and placement logistics may be coordinated as part of the concrete phase.
Do you coordinate with the plumber?
Yes. Under-slab plumbing, sleeves and penetrations should be coordinated before inspection and concrete placement.
How long before framing can begin?
Framing timing depends on concrete strength development, weather, wall height, anchor requirements and the project's inspection schedule.
Can you build attached and detached ADU foundations?
Yes. Both attached and detached foundations can be constructed when access, plans and site conditions are suitable.
Can you work with owner-builders?
Yes, provided responsibilities for plans, permits, inspections, scheduling and trade coordination are clearly defined before work begins.
Can you build stem walls and grade beams?
Yes. Reinforced stem walls, continuous footings and grade beams may be built according to approved plans.
What concrete PSI is used?
The required compressive strength is specified by the engineer or project documents. The approved mix should be confirmed before placement.
Can you modify an existing foundation for a garage conversion?
Potentially. Existing conditions must be evaluated and the work should follow approved structural details.
What do you need to prepare an estimate?
Provide the project address, approved plans, structural details, soils information when applicable, desired schedule, access information and current site photos.
ADU Foundation Construction Throughout San Diego County
Serving San Diego, Poway, Scripps Ranch, Rancho Bernardo, Rancho Peñasquitos, Carmel Valley, La Jolla, Del Mar, Encinitas, Carlsbad, Escondido, El Cajon, Chula Vista, Oceanside, Vista and surrounding communities.
Send Us Your Plans and Project Details
Tell us about the ADU type, approximate size, plan status, property access and expected construction schedule.
858-215-0821
functionalcartistry@gmail.com
California License #1032089